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    Re: Calculator Recommendations (Ageton Classic)
    From: Hewitt Schlereth
    Date: 2017 Sep 11, 13:36 -0700
    Greg, thank you for the (2!!) 'mention in dispatches' 


    On Sep 11, 2017, at 12:33 PM, Greg Rudzinski <NoReply_Rudzinski@fer3.com> wrote:


    Below is how I rank the tables that I use for sight reduction. (any trig pocket calculator will out perform any of the tables listed.)

    Table Ranking: 1.excellent, 2. very good, 3. good

          1. Schlereth Pub 229  (+ one minute precision,+ compact, ++ very quick, - long intercepts, -interpolation)

          1. Dreisonstock Pub 208   (+one minute precision, + compact, ++very quick, - long intercepts, -second table look-up)

          1. Weem's Line of Position Book (+one minute precision, + compact, +very quick, +azimuth diagram, -long intercepts, -second table look-up) 

          1. Ageton Classic (+one minute precision, +very compact, +short intercepts, + quick )

          1. Hav Doniol (+one minute precision, ++very compact, +short intercepts, +no rules, +quick, -extra arithmetic) *

          2. Schlereth Classic Trig Log (+one minute precision, +compact, +short intercept, +quick, - sin cos log sums) 

          2. Pub 249 (+one minute precision, ++very quick, -long intercepts, -interpolation, - bulky)

          3. Pub 229 (++ tenth of a minute precision, + quick, -long intercepts, -interpolation, - -very bulky)

          3. Ageton Pub 211 (+0.5 minute of precision, +short intercept, +compact, - extra rules, - - requires form )

    *Hav Doniol is the only one minute precision sight reduction method compact enough to fit in a wallet so gets highest rank for emergency sight reduction.

    Greg Rudzinski

    From: Tony Oz
    Date: 2017 Sep 11, 08:40 -0700


    Greg said:

    The Ageton Classic is not a derivitive of the the Ageton Pub 211 short table so is not subject to the errors you mention. The Ageton Classic method simply substitutes the Ageton Pub 211 log cosecant (A) and log secant (B) for log sine and log cosine when performing sight reduction using the law of cosine formulae. The Ageton Pub 211 method splits the navigational triagle into two right triangles. The Ageton Classic does not.

    I wish someone knowledgeable would finish the SR article on wikipedia - making an overview with all the strengths and weaknesses of the SR methods in existence.

    Thank you in advance.




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